62 Yew-Trees of Great Britain and Ireland 



as great as, and in many instances much greater 

 than, that of young trees. 



Sir R. Christison held with De Candolle that 

 there was diminution of growth in old trees, but 

 then he took as the proper point of measurement 

 the ground-line, which, as I have shown, leads to 

 considerable confusion. Thus, at this point, the 

 Darley Dale tree had made no growth whatever 

 during fifty-two years, while at a higher spot the 

 increase much exceeded that of young trees. There 

 is, however, in many old trees an occasional arrest 

 of growth which may last over a long period. The 

 Ankerwyke tree, near Staines, for instance, which 

 in 1882 measured 27 feet 8 inches, in 1877 had 

 reached a girth of 30 feet 5 inches; 2 feet 9 inches in 

 fifty-five years, or 1 1 inches of diameter, which ex- 

 ceeds the average growth of young trees. Since then 

 there has been an arrest of growth, as the increase 

 in 1894 was only 4 inches, or 16 lines, of diameter in 

 seventeen years. This is explained by the greater 

 part of the nourishment going to the internal trunk. 



Mr. R. Hutchison^ mentions a tree (one of 

 fifteen) at Ellon Castle, Aberdeenshire, which has 

 increased in the last thirty-six years 5 feet 6 inches 

 in eirth at i foot from the orround. This orives 

 2 2 inches of diameter in that period, or i foot in 

 1 9 "8 years, an amount of increase far exceeding 

 any recorded measurements. 



^ Trans. Eoyal Arb. Soc, 1 890. 



